Electrical stimulation of the nervous system is a technique used for restoring function to individuals with various diseases or impairments. Planar electrodes in particular are being increasingly used in neuro-stimulator devices for stimulating the central and peripheral nervous systems in humans.
Epidural spinal cord stimulation (ESCS), for example, includes electrical stimulation to the dorsal roots and/or the dorsal columns of the spinal cord. ESCS can be used for treating pain associated with various syndromes. Recently the combination of ESCS and partial weight bearing therapy has been shown to induce significant functional gains in the over-ground gait of individuals with chronic, incomplete spinal cord injury and with very low motor scores in their lower limbs.
Epidural cortical stimulation (ECS) is used in the brain for transferring electrical stimulation via planar electrodes for therapeutic applications. ECS can be used for the treatment of a variety of disorders, such as neuropathic pain, movement disorders, Parkinson's disease, and stroke rehabilitation.
Another application of electrical stimulation of the nervous system is transcranial direct current stimulation (tDCS). tDCS is a non-invasive, painless, safe and portable technique that has been found to modulate cortical excitability. The tDCS procedure is simple and economical—that is, the procedure is an injection of a weak DC current (less than 2 mA) between the surface electrodes that are connected to a stimulation device. tDCS has also shown promising results as a potential therapy in stroke, Parkinson's disease, depression and epilepsy. The advantages of tDCS, along with its positive results, reinforce its applicability within the clinical practice.
Planar electrodes are also used in electrical stimulation for restoring and/or improving control of bladder functions. In cases of neurological diseases, for example, promising results have been shown in the restoration of continence and micturition.
Deep brain stimulation (DBS) is another application of electrical stimulation of the nervous system. DBS involves high frequency electrical stimulation of the thalamic or basal ganglia structures (e.g., subthalamic nucleus (STN) or an internal segment of the globus pallidus) for the treatment of movement disorders. DBS is rapidly emerging as an alternative to surgical lesions.
The most widely used medical implanted electrodes are those used in artificial cardiac pacemaker devices to apply electric currents to the muscles of the human heart. The primary purpose of these devices is to maintain an adequate pace and rhythm of the heart's contractions. These devices have been used since the 1960s in millions of patients around the world.